The present invention relates to an electrode apparatus preferably suitable for treating of a solution containing hazardous substances, harmful substances, and the like, which solution soaks into the soil. More particularly, the present invention relates to an electrode apparatus capable of preventing a transfer or diffusion phenomenon of the hazardous substances, harmful substances, and the like, from an environment containing a high concentration of the hazardous substances, harmful substances, and the like, such as the soil around a general waste disposal landfill or an industrial waste disposal landfill, to an environment, such as the soil, a river, an underground water vein, and the like, distant from the former environment.
At present, general waste and industrial waste are treated mainly by dumping and burying them, with them left as they are, in a general waste disposal landfill, industrial waste disposal landfill, and the like, or by incinerating them, to produce ashes, which are thereafter dumped and buried in a general waste disposal landfill, industrial waste disposal landfill, and the like. Since, however, heavy metals, such as mercury, lead, cadmium, and the like; dioxin, chloroform, cyanogen (cyanide), and other harmful inorganic or organic chemical substances ooze out of these wastes, as shown in, for example, xe2x80x9cNEW EDITION DATA GUIDE EARTH ENVIRONMENTxe2x80x9d AOKI SHOTEN, PP. 238xcx9c241, June 1995, countermeasures against them have been indispensable from the standpoint of environmental protection.
As a conventional method to protect against leakage/diffusion of these substances into the environment, for example, the aforementioned literature gave a method in which a shielding rubber sheet is spread on the bottom of a landfill, the waste is dumped thereon, and the seepage water from the waste is treated by transferring from a water-collecting tube mounted on the rubber sheet to seepage water-treating equipment; or a method in which the waste is completely sealed in concrete-made containing equipment buried in the soil. These methods are explained below by referring to FIGS. 5 and 6.
FIG. 5 is a cross section of a waste disposal landfill based on the former leakage/diffusion protection method. In this former method, a thin rubber-made shielding sheet 10, with a thickness of approximately 1xcx9c2 mm, is spread over a surface of sloping soil 9, the lower part of the slope is closed with a dam 7, and a waste 8 is dumped on the shielding sheet inside of the dam, which is then reclaimed. The seepage water containing the hazardous substances, harmful substances, and the like, which oozes out of the waste, is shielded by the shielding sheet and does not leak into the environment. The seepage water is collected from the surface of a water-collecting tube 11 and transferred to seepage-water-treating equipment 12 in which it is treated and purged, and thereafter it is released into the environment.
On the other hand, FIG. 6 is a cross section of a waste disposal landfill based on the latter leakage/diffusion protection method. The waste 8 is stored in exterior-walled equipment 16 having inside partition equipment 17. These equipments are made from concrete having unconfined compression strength of 250 kg/cm2 or above, and a thickness of 10 cm or above and 15 cm or above, respectively. The waste is then covered by a cover 14, and the waste disposal landfill is provided with equipment to prevent the inflow of natural water, such as rainwater and the like, for example, equipment for preventing the inflow of rainwater 13, an open channel 15, and the like. Thus, leakage and diffusion of the hazardous substances, harmful substances, and the like into the soil 9 can be prevented by sealing off the waste completely in such a manner as described above.
The aforementioned conventional method of treating the waste, in which a shielding rubber sheet is spread on the bottom of a disposal landfill, and the waste is dumped thereon, and the seepage water from the waste is treated by transferring from a water-collecting tube mounted on the rubber sheet to seepage water-treating equipment; or the method, in which the waste is completely sealed in concrete-made containing equipment buried under the ground, can prevent the leakage and diffusion of the hazardous substances, harmful substances, and the like, if the equipment used therein is complete. Since, however, both of the conventional methods physically intercept the seepage water and the hazardous substances, harmful substances, and the like, which are contained therein, they leak easily from a place of breakage in the equipment used, even if the equipment used is slightly damaged.
For example, in the case of the former method, there has been a problem that, since the shielding rubber sheet is damaged when waste having projections is dumped thereon, as the shielding rubber sheet is easily scratched, the seepage water leaks from a place of breakage, and consequently the hazardous substances, harmful substances, and the like, which are contained therein, leak and diffuse. In the case of the latter method, there has been a problem that leakage and diffusion of the hazardous substances, harmful substances, and the like cannot be prevented when damage, such as cracks and the like, occurs in the concrete-made equipment by an earthquake, salt damage, and the like.
An object of the present invention is to provide an electrode apparatus that has been developed in order to prevent environmental pollution by aforementioned leakage and diffusion of hazardous substances, harmful substances, and the like. That is, the electrode apparatus is one that is set around equipment, such as an aforementioned waste disposal landfill and the like, and that captures the hazardous substances, harmful substances, and the like, or renders them harmless by their oxidation/reduction reaction, to prevent them from leaking and diffusing into the ambient environment in the event of breakage of the equipment.
Other and further objects, features, and advantages of the invention will appear more fully from the following description, taken in connection with the accompanying drawings.